Satellite remote sensing techniques are widely used to measure the chemical and physical state of the Earth atmosphere and of the atmospheres of other planets. These techniques rely on the measurement of the atmospheric spectrum, in a variety of spectral ranges. In particular, remote sensing measurements of the atmospheric and Earth emitted radiation are performed in the Infrared and Far-Infrared spectral regions, where most of the black body emission at their temperatures is located. To extract information from these measurements on the atmospheric state, very accurate knowledge of the spectroscopy of the atmospheric major and minor gases is required. The retrieval of the vertical profiles of temperature and atmospheric constituents is usually performed by fitting to the observations a full-physics model taking into account emission and absorption of all molecules. As a consequence the quality of the retrievals is directly linked to the availability and accuracy of the spectroscopic parameters. MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) was a Fourier transform spectrometer designed for the measurement of the Earth atmospheric limb emission in the thermal infrared (TIR) spectral range (685-2410 cm-1). It flew onboard the polar orbiting ENVISAT satellite for approximately 10 years, from June 2002 to April 2012, performing measurements during both day and night with relatively high spectral resolution (0.025 cm-1 in the first part of the mission and 0.0625 cm-1 in the second part). MIPAS/ENVISAT measurements represent a unique database for the study of the vertical distribution and time variation of the atmospheric composition on a global scale with data on more than 20 minor atmospheric constituents. On top of that, the high resolution of MIPAS measurements has provided a unique benchmark for the accuracy of current spectroscopic data. FORUM (Far-infrared-Outgoing-Radiation Understanding and Monitoring) is a new sounder selected by ESA for the phase A studies for the selection of the future Earth Explorer 9 mission. It has been designed to measure the complete spectrum of the Earth outgoing long wave radiation from space including the FIR (Far InfraRed) spectral region for the first time ever. The instrument will measure the top of the atmosphere radiation SESSION V: Spectroscopy of the Terrestrial Atmosphere in the FIR TIR spectral regions (from 100 to 1600 cm-1) with a spectral resolution of 0.3 cm-1. On top of that, FORUM will provide information on the vertical distribution of water vapour, temperature and other minor constituents. The exploitation of the FIR spectral range (100-667 cm-1) poses new requirements for the knowledge of the spectroscopy in this so-far unexploited spectral region. Here we will report some of the results of spectroscopic studies driven by MIPAS and the results of the sensitivity studies to spectroscopic data performed for the FORUM proposal.
Satellite Remote Sensing of the Atmosphere: Past (MIPAS) and Future (FORUM) Challenges
B M Dinelli;
2018
Abstract
Satellite remote sensing techniques are widely used to measure the chemical and physical state of the Earth atmosphere and of the atmospheres of other planets. These techniques rely on the measurement of the atmospheric spectrum, in a variety of spectral ranges. In particular, remote sensing measurements of the atmospheric and Earth emitted radiation are performed in the Infrared and Far-Infrared spectral regions, where most of the black body emission at their temperatures is located. To extract information from these measurements on the atmospheric state, very accurate knowledge of the spectroscopy of the atmospheric major and minor gases is required. The retrieval of the vertical profiles of temperature and atmospheric constituents is usually performed by fitting to the observations a full-physics model taking into account emission and absorption of all molecules. As a consequence the quality of the retrievals is directly linked to the availability and accuracy of the spectroscopic parameters. MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) was a Fourier transform spectrometer designed for the measurement of the Earth atmospheric limb emission in the thermal infrared (TIR) spectral range (685-2410 cm-1). It flew onboard the polar orbiting ENVISAT satellite for approximately 10 years, from June 2002 to April 2012, performing measurements during both day and night with relatively high spectral resolution (0.025 cm-1 in the first part of the mission and 0.0625 cm-1 in the second part). MIPAS/ENVISAT measurements represent a unique database for the study of the vertical distribution and time variation of the atmospheric composition on a global scale with data on more than 20 minor atmospheric constituents. On top of that, the high resolution of MIPAS measurements has provided a unique benchmark for the accuracy of current spectroscopic data. FORUM (Far-infrared-Outgoing-Radiation Understanding and Monitoring) is a new sounder selected by ESA for the phase A studies for the selection of the future Earth Explorer 9 mission. It has been designed to measure the complete spectrum of the Earth outgoing long wave radiation from space including the FIR (Far InfraRed) spectral region for the first time ever. The instrument will measure the top of the atmosphere radiation SESSION V: Spectroscopy of the Terrestrial Atmosphere in the FIR TIR spectral regions (from 100 to 1600 cm-1) with a spectral resolution of 0.3 cm-1. On top of that, FORUM will provide information on the vertical distribution of water vapour, temperature and other minor constituents. The exploitation of the FIR spectral range (100-667 cm-1) poses new requirements for the knowledge of the spectroscopy in this so-far unexploited spectral region. Here we will report some of the results of spectroscopic studies driven by MIPAS and the results of the sensitivity studies to spectroscopic data performed for the FORUM proposal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
